<!DOCTYPE html>
<html>
	<head>
		<meta charset="UTF-8">
		<title>五子棋</title>
		<style type="text/css">
			canvas {
				display: block;
				margin: 50px auto;
				box-shadow: -2px -2px 2px #EFEFEF, 5px 5px 5px #B9B9B9;
				cursor: pointer;
			}
			.btn-wrap {
				display: flex;
				flex-direction: row;
				justify-content: center;
			}
			.btn-wrap div {
				margin: 0 10px;
			}
			div>span {
				display: inline-block;
				padding: 10px 20px;
				color: #FFFFFF;
				background-color: #EE82EE;
				border-radius: 5px;
				cursor: pointer;
			}
			div.unable span {
				background: #D6D6D4;
				color: #ADACAA;
			}
			#result-wrap {
				text-align: center;
			}
		</style>


	</head>
	<body>
		<h3 id="result-wrap">--益智五子棋--</h3>
		<canvas id="chess" width="450px" height="450px"></canvas>
		<div id="btn-wrap">
			<div id="restart" class="restart">
				<span>重新开始</span>
			</div>
			<div id="goback" class="goback unable">
				<span>悔棋</span>
			</div>
			<div id="return" class="return unable">
				<span>撤销悔棋</span>
			</div>
		</div>
		<script type="text/javascript">
			var over = false;
			var me = true;	//我
			var _nowi = 0, _nowj = 0; //记录自己下棋的坐标
			var _compi = 0, _compj = 0; //记录计算机当前下棋的坐标
			var _myWin = [], _compWin = []; //记录我，计算机赢的情况
			var backAble = false, returnAble = false;    //是否悔棋，是否撤销悔棋
			var resultTxt = document.getElementById("result-wrap");
			var chressBord = []; //棋盘
			for (var i = 0; i < 15; i++) {
				chressBord[i] = [];
				for (var j = 0; j < 15; j++) {
					chressBord[i][j] = 0;
				}
			}
			//赢法的统计数组
			var myWin = [];
			var computerWin = [];
			//赢法数组
			var wins = [];
			for (var i = 0; i < 15; i++) {
				wins[i] = [];
				for (var j = 0; j < 15; j++) {
					wins[i][j] = [];
				}
			}
			var count = 0; //赢法总数
			//横线赢法
			for (var i = 0; i < 15; i++) {
				for (var j = 0; j <11; j++) {
					for (var k = 0; k < 5; k++) {
						wins[i][j+k][count] = true;
					}
					count++;
				}
			}
			console.log(wins)
			 //竖线赢法
			for (var i = 0; i < 15; i++) {
				for (var j = 0; j <11; j++) {
					for (var k = 0; k < 5; k++) {
						wins[j+k][i][count] = true;
					}
					count++;
				}
			}
			//正斜线赢法
			for (var i = 0; i < 11; i++) {
				for (var j = 0; j <11; j++) {
					for (var k = 0; k < 5; k++) {
						wins[i+k][j+k][count] = true;
					}
					count++;
				}
			}
			//反斜线赢法
			for (var i = 0; i < 11; i++) {
				for (var j = 14; j > 3; j--) {
					for (var k = 0; k < 5; k++) {
						wins[i+k][j-k][count] = true;
					}
					count++;
				}
			}
			// debugger;
			for (var i = 0; i < count; i++) {
				myWin[i] = 0;
				_myWin[i] = 0;
				computerWin[i] = 0;
				_compWin[i] = 0;
			}
			var chess = document.getElementById("chess");
			var context = chess.getContext('2d');
			context.strokeStyle = '#bfbfbf';	//边框颜色
			var backbtn = document.getElementById("goback");
			var returnbtn = document.getElementById("return");
			window.onload = function() {
				drawChessBoard(); // 画棋盘
			}
			document.getElementById("restart").onclick = function(){
				window.location.reload();
			}
			// 我，下棋
			chess.onclick = function(e){
				if(over){    //结束
					return;
				}
				if(!me){    //不该我
					return;
				}
				// 设置悔棋功能可用
				backbtn.className = backbtn.className.replace(new
				RegExp("(\\s|^)unable(\\s|$)")," ");
				var x = e.offsetX;
				var y = e.offsetY;
				var i = Math.floor(x / 30);
				var j = Math.floor(y / 30);
				_nowi = i;
				_nowj = j;
				if(chressBord[i][j] == 0){
					oneStep(i,j,me);
					chressBord[i][j] = 1; //我，已占位置

					for (var k = 0; k < count; k++) { // 将可能赢的情况都加1
						if(wins[i][j][k]){
							 // debugger;
							myWin[k]++;
							_compWin[k] = computerWin[k];
							computerWin[k] = 6; //这个位置对方不可能赢了
							if(myWin[k] == 5){
								resultTxt.innerHTML = '恭喜，你赢了！';
								over = true;
							}
						}
					}
					if(!over){
						me = !me;
						computerAI();
					}
				}
			}
			 // 悔棋
			backbtn.onclick = function(e){
				if(!backAble) { return;}
				over = false;
				me = true;
				 // resultTxt.innerHTML = 'o(╯□╰)o，悔棋中';
                // 撤销悔棋功能可用
				returnbtn.className = returnbtn.className.replace( new
				RegExp("(\\s|^)unable(\\s|$)")," ");
				// 我，悔
				chressBord[_nowi][_nowj] = 0; //我，已占位置 还原
				minusStep(_nowi, _nowj); //销毁棋子

				for (var k = 0; k < count; k++) { // 将可能赢的情况都减1
					if(wins[_nowi][_nowj][k]){
						myWin[k]--;
						computerWin[k] = _compWin[k]; //这个位置对方可能赢
					}
				}
				 // 计算机相应的悔棋
				chressBord[_compi][_compj] = 0; //计算机，已占位置 还原
				minusStep(_compi, _compj);//销毁棋子

				for (var k = 0; k < count; k++) {// 将可能赢的情况都减1
					if(wins[_compi][_compj][k]){
						computerWin[k]--;
						myWin[k] = _myWin[i];//这个位置对方可能赢
					}
				}
				resultTxt.innerHTML = '--益智五子棋--';
				returnAble = true;
				backAble = false;
			}
			// 撤销悔棋
			returnbtn.onclick = function(e){
				if(!returnAble){ return;}
				// 我，撤销悔棋
				chressBord[_nowi][_nowj] = 1;//我，已占位置
				oneStep(_nowi,_nowj,me);
				for (var k = 0; k < count; k++) {
					if(wins[_nowi][_nowj][k]){
						myWin[k]++;
						_compWin[k] = computerWin[k];
						computerWin[k] = 6;//这个位置对方不可能赢
					}
					if(myWin[k] == 5){
						resultTxt.innerHTML = '恭喜，你赢了！';
						over = true;
					}
				}
				// 计算机撤销相应的悔棋
				chressBord[_compi][_compj] = 2;//计算机，已占位置
				oneStep(_compi,_compj,false);
				for (var k = 0; k < count; k++) {// 将可能赢的情况都减1
					if(wins[_compi][_compj][k]){
						computerWin[k]++;
						_myWin[k] = myWin[k];
						myWin[k] = 6;//这个位置对方不可能赢
					}
					if(computerWin[k] == 5){
						resultTxt.innerHTML = 'o(╯□╰)o，计算机赢了，继续加油哦！';
						over = true;
					}
				}
				returnbtn.className += '' + 'unable';
				returnAble = false;
				backAble = true;
			}

			// 计算机下棋
			var computerAI = function(){
				var myScore = [];
				var computerScore = [];
				var max = 0;
				var u =0, v = 0;
				for (var i = 0; i < 15; i++) {
					myScore[i] = [];
					computerScore[i] = [];
					for (var j = 0; j < 15; j++) {
						myScore[i][j] = 0;
						computerScore[i][j] = 0;
					}
				}
				for (var i = 0; i < 15; i++) {
					for (var j = 0; j < 15; j++) {
						if(chressBord[i][j] == 0){
							for (var k = 0; k < count; k++) {
								if(wins[i][j][k]){
									if(myWin[k] == 1){
										myScore[i][j] += 200;
									}else if(myWin[k] == 2){
										myScore[i][j] += 400;
									}
									else if(myWin[k] == 3){
										myScore[i][j] += 2000;
									}
									else if(myWin[k] == 4){
										myScore[i][j] += 10000;
									}

									if(computerWin[k] == 1){
										computerScore[i][j] += 220;
									}else if(computerWin[k] == 2){
										computerScore[i][j] += 420;
									}
									else if(computerWin[k] == 3){
										computerScore[i][j] += 2100;
									}
									else if(computerWin[k] == 4){
										computerScore[i][j] += 20000;
									}
								}
							}

							if(myScore[i][j] > max){
								max = myScore[i][j];
								u = i;
								v = j;
							}else if(myScore[i][j] == max){
								if(computerScore[i][j]>computerScore[u][v]){
									u = i;
									v = j;
								}
							}

							if(computerScore[i][j] > max){
								max = computerScore[i][j];
								u = i;
								v = j;
							}else if(computerScore[i][j] == max){
								if(myScore[i][j]>myScore[u][v]){
									u = i;
									v = j;
								}
							}
						}
					}
				}
				_compi = u;
				_compj = v;
				oneStep(u,v,false);chressBord[u][v] = 2; //计算机占据位置
				for (var k = 0; k < count; k++) {
					if(wins[u][v][k]){
						computerWin[k]++;
						_myWin[k] = myWin[k];
						myWin[k] = 6; //这个位置对方不可能赢了
						if(computerWin[k] == 5){
							resultTxt.innerHTML = 'o(╯□╰)o，计算机赢了，继续加油哦！';
							over = true;
						}
					}
				}
				if(!over){
					me = !me;
				}
				backAble = true;
				returnAble = false;
				var hasClass = new RegExp('unable').test('' +
				returnbtn.className + '');
				if(hasClass) {
					returnbtn.className += '' + 'unable';
				}
			}
			//绘画棋盘
			var drawChessBoard = function(){
				for (var i = 0; i < 15; i++) {
				    //横线
					context.moveTo(15 + i * 30 , 15);
					context.lineTo(15 + i * 30 , 435);
					context.stroke();
					//纵线
					context.moveTo(15 , 15 + i * 30);
					context.lineTo(435 , 15 + i * 30);
					context.stroke();
				}
			}
			//画棋子
			var oneStep = function(i,j,me) {
				context.beginPath();
				context.arc(15 +i * 30, 15 + j * 30, 13, 0, 2 * Math.PI);// 画圆
				context.closePath();
				//渐变
				var gradient = context.createRadialGradient(15 + i * 30
				+ 2, 15 + j * 30 - 2, 13, 15 + i * 30 + 2, 15 + j * 30 -
				2, 0);
				if(me){
					gradient.addColorStop(0,'#0a0a0a');
					gradient.addColorStop(1,'#636766');
				}else{
					gradient.addColorStop(0,'#d1d1d1');
					gradient.addColorStop(1,'#f9f9f9')
				}
				context.fillStyle = gradient;
				context.fill();
			}
			//销毁棋子
			var minusStep = function(i,j){
				 //擦除该圆
				context.clearRect((i) * 30, (j) * 30, 30, 30);
				// 重画该圆周围的格子
				context.beginPath();
				context.moveTo(15+i*30, j*30);
				context.lineTo(15+i*30, j*30 + 30);
				context.moveTo(i*30, j*30+15);
				context.lineTo((i+1)*30, j*30+15);

				context.stroke();
			}
		</script>
	</body>
</html>